module AuthenticatedTestHelper
    # Sets the current user in the session from the user fixtures.
    def login_as(user)
        @request.session[:user] = user ? users(user).id : nil
    end

    def content_type(type)
        @request.env['Content-Type'] = type
    end

    def accept(accept)
        @request.env["HTTP_ACCEPT"] = accept
    end

    def authorize_as(user)
        if user
            @request.env["HTTP_AUTHORIZATION"] = "Basic #{Base64.encode64("#{users(user).login}:test")}"
            accept       'application/xml'
            content_type 'application/xml'
        else
            @request.env["HTTP_AUTHORIZATION"] = nil
            accept       nil
            content_type nil
        end
    end

    # http://project.ioni.st/post/217#post-217
    #
    #  def test_new_publication
    #    assert_difference(Publication, :count) do
    #      post :create, :publication => {...}
    #      # ...
    #    end
    #  end
    #
    def assert_difference(object, method = nil, difference = 1)
        initial_value = object.send(method)
        yield
        assert_equal initial_value + difference, object.send(method), "#{object}##{method}"
    end

    def assert_no_difference(object, method, &block)
        assert_difference object, method, 0, &block
    end

    # Assert the block redirects to the login
    #
    #   assert_requires_login(:bob) { |c| c.get :edit, :id => 1 }
    #
    def assert_requires_login(login = nil)
        yield HttpLoginProxy.new(self, login)
    end

    def assert_http_authentication_required(login = nil)
        yield XmlLoginProxy.new(self, login)
    end

    def reset!(*instance_vars)
        instance_vars = [:controller, :request, :response] unless instance_vars.any?
        instance_vars.collect! { |v| "@#{v}".to_sym }
        instance_vars.each do |var|
            instance_variable_set(var, instance_variable_get(var).class.new)
        end
    end
end

class BaseLoginProxy
    attr_reader :controller
    attr_reader :options
    def initialize(controller, login)
        @controller = controller
        @login      = login
    end

    private
    def authenticated
        raise NotImplementedError
    end

    def check
        raise NotImplementedError
    end

    def method_missing(method, *args)
        @controller.reset!
        authenticate
        @controller.send(method, *args)
        check
    end
end

class HttpLoginProxy < BaseLoginProxy
    protected
    def authenticate
        @controller.login_as @login if @login
    end

    def check
        @controller.assert_redirected_to :controller => 'sessions', :action => 'new'
    end
end

class XmlLoginProxy < BaseLoginProxy
    protected
    def authenticate
        @controller.accept 'application/xml'
        @controller.authorize_as @login if @login
    end

    def check
        @controller.assert_response 401
    end
end
